arch/sparc/kernel/sun4m_smp.c

   1 /*
   2  *  sun4m SMP support.
   3  *
   4  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   5  */
   6
   7 #include <linux/interrupt.h>
   8 #include <linux/profile.h>
   9 #include <linux/delay.h>
  10 #include <linux/cpu.h>
  11
  12 #include <asm/cacheflush.h>
  13 #include <asm/tlbflush.h>
  14
  15 #include "irq.h"
  16 #include "kernel.h"
  17
  18 #define IRQ_CROSS_CALL          15
  19
  20 static inline unsigned long
  21 swap_ulong(volatile unsigned long *ptr, unsigned long val)
  22 {
  23         __asm__ __volatile__("swap [%1], %0\n\t" :
  24                              "=&r" (val), "=&r" (ptr) :
  25                              "0" (val), "1" (ptr));
  26         return val;
  27 }
  28
  29 static void smp_setup_percpu_timer(void);
  30
  31 void __cpuinit smp4m_callin(void)
  32 {
  33         int cpuid = hard_smp_processor_id();
  34
  35         local_flush_cache_all();
  36         local_flush_tlb_all();
  37
  38         notify_cpu_starting(cpuid);
  39
  40         /* Get our local ticker going. */
  41         smp_setup_percpu_timer();
  42
  43         calibrate_delay();
  44         smp_store_cpu_info(cpuid);
  45
  46         local_flush_cache_all();
  47         local_flush_tlb_all();
  48
  49         /*
  50          * Unblock the master CPU _only_ when the scheduler state
  51          * of all secondary CPUs will be up-to-date, so after
  52          * the SMP initialization the master will be just allowed
  53          * to call the scheduler code.
  54          */
  55         /* Allow master to continue. */
  56         swap_ulong(&cpu_callin_map[cpuid], 1);
  57
  58         /* XXX: What's up with all the flushes? */
  59         local_flush_cache_all();
  60         local_flush_tlb_all();
  61
  62         cpu_probe();
  63
  64         /* Fix idle thread fields. */
  65         __asm__ __volatile__("ld [%0], %%g6\n\t"
  66                              : : "r" (&current_set[cpuid])
  67                              : "memory" /* paranoid */);
  68
  69         /* Attach to the address space of init_task. */
  70         atomic_inc(&init_mm.mm_count);
  71         current->active_mm = &init_mm;
  72
  73         while (!cpu_isset(cpuid, smp_commenced_mask))
  74                 mb();
  75
  76         local_irq_enable();
  77
  78         set_cpu_online(cpuid, true);
  79 }
  80
  81 /*
  82  *      Cycle through the processors asking the PROM to start each one.
  83  */
  84 void __init smp4m_boot_cpus(void)
  85 {
  86         smp_setup_percpu_timer();
  87         local_flush_cache_all();
  88 }
  89
  90 int __cpuinit smp4m_boot_one_cpu(int i)
  91 {
  92         unsigned long *entry = &sun4m_cpu_startup;
  93         struct task_struct *p;
  94         int timeout;
  95         int cpu_node;
  96
  97         cpu_find_by_mid(i, &cpu_node);
  98
  99         /* Cook up an idler for this guy. */
 100         p = fork_idle(i);
 101         current_set[i] = task_thread_info(p);
 102         /* See trampoline.S for details... */
 103         entry += ((i - 1) * 3);
 104
 105         /*
 106          * Initialize the contexts table
 107          * Since the call to prom_startcpu() trashes the structure,
 108          * we need to re-initialize it for each cpu
 109          */
 110         smp_penguin_ctable.which_io = 0;
 111         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 112         smp_penguin_ctable.reg_size = 0;
 113
 114         /* whirrr, whirrr, whirrrrrrrrr... */
 115         printk(KERN_INFO "Starting CPU %d at %p\n", i, entry);
 116         local_flush_cache_all();
 117         prom_startcpu(cpu_node, &smp_penguin_ctable, 0, (char *)entry);
 118
 119         /* wheee... it's going... */
 120         for (timeout = 0; timeout < 10000; timeout++) {
 121                 if (cpu_callin_map[i])
 122                         break;
 123                 udelay(200);
 124         }
 125
 126         if (!(cpu_callin_map[i])) {
 127                 printk(KERN_ERR "Processor %d is stuck.\n", i);
 128                 return -ENODEV;
 129         }
 130
 131         local_flush_cache_all();
 132         return 0;
 133 }
 134
 135 void __init smp4m_smp_done(void)
 136 {
 137         int i, first;
 138         int *prev;
 139
 140         /* setup cpu list for irq rotation */
 141         first = 0;
 142         prev = &first;
 143         for_each_online_cpu(i) {
 144                 *prev = i;
 145                 prev = &cpu_data(i).next;
 146         }
 147         *prev = first;
 148         local_flush_cache_all();
 149
 150         /* Ok, they are spinning and ready to go. */
 151 }
 152
 153 /* At each hardware IRQ, we get this called to forward IRQ reception
 154  * to the next processor.  The caller must disable the IRQ level being
 155  * serviced globally so that there are no double interrupts received.
 156  *
 157  * XXX See sparc64 irq.c.
 158  */
 159 void smp4m_irq_rotate(int cpu)
 160 {
 161         int next = cpu_data(cpu).next;
 162
 163         if (next != cpu)
 164                 set_irq_udt(next);
 165 }
 166
 167 static struct smp_funcall {
 168         smpfunc_t func;
 169         unsigned long arg1;
 170         unsigned long arg2;
 171         unsigned long arg3;
 172         unsigned long arg4;
 173         unsigned long arg5;
 174         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 175         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 176 } ccall_info;
 177
 178 static DEFINE_SPINLOCK(cross_call_lock);
 179
 180 /* Cross calls must be serialized, at least currently. */
 181 static void smp4m_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 182                              unsigned long arg2, unsigned long arg3,
 183                              unsigned long arg4)
 184 {
 185                 register int ncpus = SUN4M_NCPUS;
 186                 unsigned long flags;
 187
 188                 spin_lock_irqsave(&cross_call_lock, flags);
 189
 190                 /* Init function glue. */
 191                 ccall_info.func = func;
 192                 ccall_info.arg1 = arg1;
 193                 ccall_info.arg2 = arg2;
 194                 ccall_info.arg3 = arg3;
 195                 ccall_info.arg4 = arg4;
 196                 ccall_info.arg5 = 0;
 197
 198                 /* Init receive/complete mapping, plus fire the IPI's off. */
 199                 {
 200                         register int i;
 201
 202                         cpu_clear(smp_processor_id(), mask);
 203                         cpus_and(mask, cpu_online_map, mask);
 204                         for (i = 0; i < ncpus; i++) {
 205                                 if (cpu_isset(i, mask)) {
 206                                         ccall_info.processors_in[i] = 0;
 207                                         ccall_info.processors_out[i] = 0;
 208                                         set_cpu_int(i, IRQ_CROSS_CALL);
 209                                 } else {
 210                                         ccall_info.processors_in[i] = 1;
 211                                         ccall_info.processors_out[i] = 1;
 212                                 }
 213                         }
 214                 }
 215
 216                 {
 217                         register int i;
 218
 219                         i = 0;
 220                         do {
 221                                 if (!cpu_isset(i, mask))
 222                                         continue;
 223                                 while (!ccall_info.processors_in[i])
 224                                         barrier();
 225                         } while (++i < ncpus);
 226
 227                         i = 0;
 228                         do {
 229                                 if (!cpu_isset(i, mask))
 230                                         continue;
 231                                 while (!ccall_info.processors_out[i])
 232                                         barrier();
 233                         } while (++i < ncpus);
 234                 }
 235                 spin_unlock_irqrestore(&cross_call_lock, flags);
 236 }
 237
 238 /* Running cross calls. */
 239 void smp4m_cross_call_irq(void)
 240 {
 241         int i = smp_processor_id();
 242
 243         ccall_info.processors_in[i] = 1;
 244         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 245                         ccall_info.arg4, ccall_info.arg5);
 246         ccall_info.processors_out[i] = 1;
 247 }
 248
 249 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 250 {
 251         struct pt_regs *old_regs;
 252         int cpu = smp_processor_id();
 253
 254         old_regs = set_irq_regs(regs);
 255
 256         sun4m_clear_profile_irq(cpu);
 257
 258         profile_tick(CPU_PROFILING);
 259
 260         if (!--prof_counter(cpu)) {
 261                 int user = user_mode(regs);
 262
 263                 irq_enter();
 264                 update_process_times(user);
 265                 irq_exit();
 266
 267                 prof_counter(cpu) = prof_multiplier(cpu);
 268         }
 269         set_irq_regs(old_regs);
 270 }
 271
 272 static void __cpuinit smp_setup_percpu_timer(void)
 273 {
 274         int cpu = smp_processor_id();
 275
 276         prof_counter(cpu) = prof_multiplier(cpu) = 1;
 277         load_profile_irq(cpu, lvl14_resolution);
 278
 279         if (cpu == boot_cpu_id)
 280                 enable_pil_irq(14);
 281 }
 282
 283 static void __init smp4m_blackbox_id(unsigned *addr)
 284 {
 285         int rd = *addr & 0x3e000000;
 286         int rs1 = rd >> 11;
 287
 288         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 289         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 290         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 291 }
 292
 293 static void __init smp4m_blackbox_current(unsigned *addr)
 294 {
 295         int rd = *addr & 0x3e000000;
 296         int rs1 = rd >> 11;
 297
 298         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 299         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 300         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
 301 }
 302
 303 void __init sun4m_init_smp(void)
 304 {
 305         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 306         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 307         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 308         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 309 }